AU2003204036A1 - A conveyor - Google Patents

Description

-1-

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: Actual Inventor: Address for Service:

CCN:

Invention Title: David Stanley Hoyle David Stanley Hoyle Baldwin Shelston Waters MARGARET STREET SYDNEY NSW 2000 3710000352 A CONVEYOR The following statement is a full description of this invention, including the best method of performing it known to me:- File: 38868AUP00 500155146_1.DOC/5844 A CONVEYOR TECHNICAL FIELD The present invention relates to conveyors adapted to provide an even rate of material supply from an end or drop off zone of the conveyor, and in particular, but not exclusively, to a conveyor for use with agricultural spreaders.

BACKGROUND ART Conveyors are an important component of many agricultural spreaders which are used extensively in agricultural industries to distribute materials such as fertiliser/manure over land.

An agricultural spreader may include a bin or trailer unit in which material to be spread is stored. The conveyor belt conveys material from the bin to a drop point, where material is spread over the ground or is transferred to a distribution device, for example a spreader bar or a spinner.

On uneven ground it has been found that belt conveyors do not perform well and chain conveyors, also known as chain scraper conveyors, have been used. Here the material is deposited on a stationary tray and is pushed to a drop point by a plurality of spaced apart blades or bars, hereinafter called scraper bars, which are carried between a pair of chains running down either side of the tray.

Chain conveyors may also have inherent disadvantages. When one of the scraper bars reaches the drop-off point, substantially all of the material between that scraper bar and the next on the chain may tend to flow over the drop-off point in an unrestricted manner, resulting in an uneven supply of material to the surface or the distribution device which the conveyor is feeding. This may cause some areas of the surface to receive excessive amounts of material while others receive less than is ideal.

If the conveyor is used in spreading fertiliser onto crops for example, the excessive concentrations of fertiliser may cause damage to the plants. At the same time other areas may not receive adequate fertiliser for maximum growth.

OBJECT OF THE INVENTION It is an object of a preferred embodiment of the invention to provide a conveyor which will overcome or ameliorate problems with such conveyors at present, or at least one which will provide the public with a useful choice.

Other objects of the invention will become apparent from the following description which is given by way of example only.

SUMMARY OF THE INVENTION According to a first aspect of the present invention there is provided a conveyor to deliver material from a material supply means to a material receiving area, the conveyor including a material support surface and a drop-off zone which, in use, is positioned above said material receiving area, the conveyor further including a plurality of spaced apart material transfer means extending substantially across a width of said material support surface and adapted to travel at least between said material supply means and a position at or substantially adjacent an end of said drop-off zone distal said material supply means, thereby transferring material from said material supply means to said drop off zone, wherein said drop-off zone includes a substantially planar surface which includes at least a pair of converging sides and said material transfer means, in use, push material over at least one of said sides as they move over said drop-off zone, thereby providing material to said material receiving area at a substantially uniform rate.

Preferably, said drop off zone may be integrally formed with said material support surface.

Preferably, said drop off zone may be discrete from but connectable to said material support surface.

Preferably, said conveyor may be adapted to convey agricultural material.

Preferably, said material receiving area may include an entry to one or more spinners, blending bins and/or blowers.

Preferably, said material support surface may be a substantially flat tray or platform.

Preferably, the material transfer means may include a plurality of spaced apart scraper bars, a longitudinal axis of each said scraper bar is orientated substantially perpendicular to a longitudinal axis of said material support surface.

Preferably, the converging sides of said drop-off zone may form an included angle of substantially 800.

Preferably, the sides of said drop-off zone may converge to an apex.

Preferably, the drop-off zone may be substantially the same length as the spacing between successive material transfer means.

According to a second aspect of the present invention there is provided a conveyor to deliver material from a material supply means to a material receiving area which, in use, is positioned below said conveyor, the conveyor including a material support surface, a material supply means proximate a first end of said material support surface and a drop-off zone at an opposite end of said material support surface, the drop-off zone including first and second distinct substantially flat or planar surfaces which together form a segmented convex surface extending, in use, below said material support surface, the conveyor further including a plurality of spaced apart material transfer means extending across the width of said material support surface and adapted to travel at least between said material supply means and a position at or substantially adjacent an end of said drop-off zone distal said material supply means, thereby transferring material from said material supply means to said drop off zone, wherein, in use, said material transfer means follow a path relative to said drop off zone such that said material drops between said material transfer means and said surfaces to said material receiving area at a substantially uniform rate.

Preferably, the plane of said first distinct surface may be angled at between substantially 1400 and 1300 to the plane of said material support surface.

Preferably, the plane of said first distinct surface may be angled at substantially 1350 to the plane of said material support surface.

Preferably, the transverse clearance between said material transfer means and the centre of said first distinct surface may be between substantially 10Omm and Preferably, the transverse clearance between said material transfer means and the centre of said first distinct surface may be substantially 13mm.

Preferably, the plane of the second distinct surface may be angled at between substantially 155" and 1650 to the plane of said first distinct surface.

Preferably, the plane of said second distinct surface may be angled at substantially 160" to the plane of said first distinct surface.

Preferably, the transverse clearance between said material transfer means and the centre of said second distinct surface may be between substantially 10mm and Preferably, the transverse clearance between said material transfer means and the centre of said second distinct surface may be substantially Preferably, said drop off zone may further include a third distinct surface substantially adjacent said second distinct surface.

Preferably, the plane of said third distinct surface may be angled at between substantially 1400 and 130" to the plane of said second distinct surface.

Preferably, the plane of said third distinct surface may be angled at substantially 135" to the plane of said second distinct surface.

Preferably, or more of said distinct surfaces may be integrally formed.

Preferably, one or more of said distinct surfaces may be formed integrally with said material support means.

Preferably, one or more of said distinct surfaces may be a discrete element connectable to at least one of an other of said distinct surfaces or said material support means.

Preferably, said conveyor may be adapted to convey agricultural material.

Preferably, said material receiving area may include an entry to one or more spinners, blending bins and/or blowers.

Preferably, said material support surface may be a substantially flat tray or platform.

Preferably, said material transfer means may include a plurality of spaced apart scraper bars, a longitudinal axis of each said scraper bar is orientated substantially perpendicular to a longitudinal axis of said material support surface.

Preferably, said scraper bars may travel through a brushing means located at an end of said drop-off zone distal said material support surface.

Preferably, the base of said brushing means may be inside the path of said scraper bars as said scraper bars travel over said drop off zone, and bristles of said brushing means extend into the path of said scraper bars.

According to a third aspect of the present invention there is provided a conveyor to deliver material from a material supply means to a material receiving area which, in use, is positioned below said conveyor, the conveyor including a material support surface, a material supply means proximate a first end of said material support surface and a drop-off zone at an opposite end of said material support surface, the conveyor further including a plurality of spaced apart material transfer means extending across the width of said material support surface and adapted to travel at least between said material supply means and a position at or substantially adjacent an end of said drop-off zone distal said material supply means, thereby transferring material from said material supply means to said drop off zone, wherein said material transfer means follow a substantially semicircular path over said drop-off zone, the drop-off zone including first and second distinct substantially flat or planar surfaces which together form a segmented convex surface extending, in use, below said material support surface, wherein the clearance between said distinct surfaces and said material support means allows said material, in use, to drop between said material transfer means and said distinct surfaces to said material receiving area at a substantially uniform rate.

Preferably, said drop off zone may further include a third distinct surface substantially adjacent said second distinct surface.

According to a still further aspect of the present invention, a conveyor (as herein defined) is substantially as herein described with reference to Figures 2A and 2B or Figure 3 of the accompanying drawings.

Other aspects of the invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1: Shows (diagrammatically) a side elevation of a chain conveyor of the prior art.

Figure 2A: Shows (diagrammatically) a side elevation of an overhead returning conveyor according to one aspect of the present invention.

Figure 2B: Shows (diagrammatically) a plan view of the drop-off plate of the conveyor of Figure 2A.

Figure 3: Shows (diagrammatically)a side elevation of an underhand returning conveyor according to a second embodiment of the present invention.

BRIEF DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION The present invention is described with reference to its use as part of an agricultural spreader. It will be appreciated by those skilled in the art however, that the conveyors of the present invention are not restricted to use in agriculture and farming but may be used in any field where a substantially constant supply of particulate material from a conveyor is required.

It will further be appreciated by those skilled in the art that the use of the term "material" in this specification may include any solid or semi-solid particulate material.

Such materials may include agricultural materials such as fowl manure, dry granular material, lime, fertilisers, pesticides and the like.

Referring first to Figure 1, a chain conveyor of the prior art, generally referenced by arrow 100, may include a material support surface, for example a generally flat platform or tray 1, onto which a fertilising material 2 is deposited by material supply means, typically a hopper or bin (not shown). The conveyor may 100 may run underneath or alternatively through the hopper or bin.

The fertilising material 2 may be conveyed to a discrete drop-off point 3 at the end of the conveyor tray 1 by a plurality of material transfer means, for example scraper bars 4, positioned adjacent and/or touching the tray 1 and extending across the width of the tray 1. The scraper bars 4 are pulled towards the drop-off point 3 by a chain 5 at either side of the scraper bars 4. The longitudinal axis of the scraper bars 4 may typically be substantially perpendicular to the longitudinal axis of the tray 1 and thus perpendicular to the mean direction of travel of the material 2 as it moves along the tray 1.

When a scraper bar 4A reaches the drop-off point 3 the packet of material 2A between the scraper bar 4A and the following scraper bar 4B may flow through the gap 6 created between the frontmost scraper bar 4A and the drop off point 3. At low feed speeds, and particularly if the material 2A has low or no effective viscosity, most or substantially all of the material 2A between the two scraper bars 4A, 4B may flow through this gap 6 to a material receiving area below (not shown) in a substantially uncontrolled manner.

Typically the material receiving area may be the inlet to a distribution device such as a blender or blower, or the top of a spinner, although in some cases an intermediate path may be used to feed such devices.

The relatively unrestricted nature of the flow of material 2A may cause most or substantially all the material 2A to flow over the drop-off point 3 before the second scraper bar 4B reaches the drop off point. This may cause an unevenness in the delivery from the conveyor 100 which may in turn cause an excess of material 2 to be deposited on the area immediately below the spreader. The material 2A between the scraper bars 4A and 4B may then be substantially exhausted causing an adjacent area to receive less than the desired amount of material 2 before the next scraper bar 4 reaches the drop off point 3 and the next packet of material 2 can begin to flow.

Referring next to Figures 2A and 2B, an over returning conveyor according to one aspect of the present invention is generally referenced by arrow 200. The conveyor 200 may include a tray surface 1 and scraper bars 4 in common with conveyors 100 of the prior art.

The plane of the scraper bars 4 may preferably be orientated at around relative to the plane of the tray surface 1, with the lower edge of the scraper 4 leading.

This orientation may assist in preventing the scraper bars 4 from lifting relative to the tray surface 1.

Rather than moving material 2 to a discrete drop-off point, as may be the case with the conveyors of the prior art, the scraper bars 4 of the present invention may convey material 2 to a substantially flat or planar, tapered drop off plate 1A, which effectively forms an extended drop off zone in which the material 2 is allowed to fall in a more uniform manner than the conveyors of the prior art.

As best seen in Figure 2B, as the material 2 is pushed over the drop-off plate 1A the material 2 near the edges 7 of the drop off-plate 1A is pushed off. As the scraper bars 4 move over the drop-off plate 1A the area available to support the material 2 may decrease substantially linearly, causing a steady flow of material 2 over the sides 7. By the time the scraper bar 4 nears the far end 8 of the drop-off plate 1A, only a small amount of material 2, if any, may remain. This last material 2 may be pushed off the end 8. In an alternative embodiment (not shown) the plate 1A may form a substantially V shape, so that the end of the plate 1A forms an apex rather than a squared off end as shown in Figure 2B.

The chain 5 and scraper bars 4 may around follow a pair of coaxial sprockets 13 located proximate the drop-off zone 9 as they loop around above the tray surface 1 and back to a hopper or other material supply means.

Preferably the included angle of the tapered sides 7 of the drop-off plate 1A may be approximately 800, although this angle may be varied as required depending on the material 2 being conveyed. Preferably the length of the drop-off plate 1A may be substantially equal to the spacing between successive scraper bars 4.

A dividing means such as a disc (not shown) may be located between the sprockets 13 in substantially the centre of the drop off plate 1A. The disc may assist in preventing material from sliding across the drop-off plate 1A, thereby assisting in maintaining an even distribution of material 2 on the drop off plate 1A, particularly if the spreader is on a slope.

Referring next to Figure 3, an underhand returning chain conveyor according to a second embodiment of the present invention is generally referenced by arrow 300.

The conveyor 300 may also include a tray surface 1 and an enlarged drop-off zone, generally referenced by arrows 9, towards which material is conveyed from a material supply means (not shown) by a plurality of scraper bars 4.

At the drop-off zone 9 the tray 1 may slope downward to form at least two, or more preferably three distinct, substantially flat or planar surfaces 10, 11, 12 which together define a segmented substantially convex shape. The first surface 10 may preferably form an interior angle A of between substantially 130" and 140" with the tray 1. The second surface 11 may preferably form an interior angle B of between substantially 155* and 1650 with the first surface 10 and the third surface 12 may preferably form an interior angle C of between substantially 130" and 1400 with the second surface 11, although angles outside this range may be used in some cases.

In a particularly preferred embodiment, the first surface 10 may form an angle A of substantially 135" with the tray 1. The second surface 11 may form an angle B of substantially 160" with the first surface 10 and the third surface 12 may from an angle C of approximately 1350 with the second surface 11.

The distinct surfaces 10, 11, 12 may be integrally formed from a single sheet of material or may be formed from two or more connectable elements. In one embodiment the surfaces 10, 11, 12 may be formed by bends in the tray 1.

The chain 5 and scraper bars 4 may follow a substantially semicircular path around a pair of coaxial sprockets 13 located proximate the drop-off zone 9, although those skilled in the art will appreciate that a series of smaller sprockets (not shown) may be provided to direct each chain 5 and the scraper bars 4 over the drop off zone 9, rather than each chain 5 following a single sprocket 13 as illustrated in the figures.

The clearance between the surfaces 10, 11, 12 and the scraper bars 4 as they rotate around the sprockets 13 may determine the space available for the material 2 to pass through, and therefore the rate and uniformity of the flow of material 2 through the drop-off zone 9 and onto the spreading devices located below.

The transverse clearance between the bottom edge of the scraper bars 4 and the middle of the surfaces 10, 11 is shown by arrows 14 and 15 respectively. The optimum values of the transverse clearances 14, 15 and the lengths of the surfaces 11, 12 may be ascertained for a given material by simple experiment, but the Applicant has found that clearance distances of between 10Omm-25mm for clearance 14 and between 10Omm-25mm for clearance distance 15 are suitable. In a particularly preferred embodiment for general fertiliser spreading applications the clearance distances 14 and may be 13mm and 10mm respectively.

Those skilled in the art will recognise that the relative angles A, B, C between the surfaces 10, 11, 12 must be selected to provide a required spacing 14, 15 between the tray surfaces 10, 11, 12 and the path of the scraper bars 4, while ensuring that the tray surfaces 10, 11, 12 remain within the radius of rotation of the scraper bars 4 as they move around the sprocket 13.

The Applicant has surprisingly found that provision of two or three distinct flat surfaces 10, 11, 12 provides a more uniform flow of material than a convex curve.

A brush 17 may be positioned with its base on the inside of the path of the chain and scraper bars 4 with its bristles pointing outward into the path of the scraper bars 4. The brush 17 may extend across the width of the scraper bars 4 and the chain 5 and may remove any residual material left on the chain 5 and scraper bars 4 after they have travelled over the drop-off zone 9. The brush 17 may ensure that the scraper bars 4 are cleaned before they travel back to the material supply means.

Preferably a dividing means such as a disc 18 may be located midway between the sprockets 13 and coaxial with the sprockets 13, and may extend through a slot (not shown) in the tray 1. The disc 18 may preferably be of slightly smaller diameter than the sprockets 13. The disc 18 may prevent material from sliding across the conveyor tray 1, thereby assisting in maintaining an even distribution of material 4 in the drop off zone 9, particularly if the spreader is on a slope.

In an alternative embodiment (not shown), one or more additional chains may be provided between the two outer drive chains 5 in order to divide the material on the conveyor tray 1 into divided streams, thereby assisting in providing an even distribution of material across the width of the conveyor 300.

Those skilled in the art will appreciate that the present invention provides a chain conveyor system which may allow material to be delivered from an end of the conveyor at a more uniform rate than the conveyors of the prior art.

Wherein the forgoing description reference has been made to specific components or integers of the invention having known equivalents then such equivalents are herein incorporated as if individually set forth.

Although the invention has been described by way of example only and with reference to possible embodiments thereof it is to be understood that modifications or improvements may be made thereto without departing from the scope of the appended claims.

Claims (29)

1. A conveyor to deliver material from a material supply means to a material receiving area, the conveyor including a material support surface and a drop-off zone which, in use, is positioned above said material receiving area, the conveyor further including a plurality of spaced apart material transfer means extending substantially across a width of said material support surface and adapted to travel at least between said material supply means and a position at or substantially adjacent an end of said drop-off zone distal said material supply means, thereby transferring material from said material supply means to said drop off zone, wherein said drop-off zone includes a substantially planar surface which includes at least a pair of converging sides and said material transfer means, in use, push material over at least one of said sides as they move over said drop-off zone, thereby providing material to said material receiving area at a substantially uniform rate.

2. The conveyor of Claim 1 wherein said drop off zone is integrally formed with said material support surface.

3. The conveyor of Claim 1 wherein said drop off zone is discrete from but connectable to said material support surface.

4. The conveyor of Claim 1, 2 or 3 wherein said conveyor is adapted to convey agricultural material. The conveyor of Claim 1, 2, 3 or 4 wherein said material receiving area includes an entry to one or more spinners, blending bins and/or blowers.

6. The conveyor of Claim 1, 2, 3, 4 or 5 wherein said material support surface is a substantially flat tray or platform.

7. The conveyor of any one of the previous claims wherein the material transfer means includes a plurality of spaced apart scraper bars, a longitudinal axis of each said scraper bar is orientated substantially perpendicular to a longitudinal axis of said material support surface.

8. The conveyor of any one of the previous claims wherein the converging sides of said drop-off zone form an included angle of substantially 800.

9. The conveyor of any one of the previous claims wherein the sides of said drop- off zone converge to an apex. The conveyor of any one of the previous claims wherein the drop-off zone is substantially the same length as the spacing between successive material transfer means.

11. A conveyor to deliver material from a material supply means to a material receiving area which, in use, is positioned below said conveyor, the conveyor including a material support surface, a material supply means proximate a first end of said material support surface and a drop-off zone at an opposite end of said material support surface, the drop-off zone including first and second distinct substantially flat or planar surfaces which together form a segmented convex surface extending, in use, below said material support surface, the conveyor further including a plurality of spaced apart material transfer means extending across the width of said material support surface and adapted to travel at least between said material supply means and a position at or substantially adjacent an end of said drop-off zone distal said material supply means, thereby transferring material from said material supply means to said drop off zone, wherein, in use, said material transfer means follow a path relative to said drop off zone such that said material drops between said material transfer means and said surfaces to said material receiving area at a substantially uniform rate.

12. The conveyor of Claim 11 wherein the plane of said first distinct surface is angled at between substantially 140 and 130* to the plane of said material support surface.

13. The conveyor of Claim 12 wherein the plane of said first distinct surface is angled at substantially 1350 to the plane of said material support surface.

14. The conveyor of any one of Claims 11 to 13 wherein the transverse clearance between said material transfer means and the centre of said first distinct surface is between substantially 10mm and The conveyor of Claim 14 wherein the transverse clearance between said material transfer means and the centre of said .first distinct surface is substantially 13mm.

16. The conveyor of any one of Claims 11 to 15 wherein the plane of the second distinct surface is angled at between substantially 1550 and 1650 to the plane of said first distinct surface.

17. The conveyor of Claim 16 wherein the plane of said second distinct surface is angled at substantially 160" to the plane of said first distinct surface.

18. The conveyor of any one of Claims 11 to 17 wherein the transverse clearance between said material transfer means and the centre of said second distinct surface is between substantially 10mm and

19. The conveyor of Claim 18 wherein the transverse clearance between said material transfer means and the centre of said second distinct surface is substantially The conveyor of any one of Claims 11 to 19 wherein said drop off zone further includes a third distinct surface substantially adjacent said second distinct surface.

21. The conveyor of Claim 20 wherein the plane of said third distinct surface is angled at between substantially 140' and 130* to the plane of said second distinct surface.

22. The conveyor of Claim 21 wherein the plane of said third distinct surface is angled at substantially 1350 to the plane of said second distinct surface.

23. The conveyor of any one of Claims 11 to 22 wherein two or more of said distinct surfaces are integrally formed.

24. The conveyor of any one of Claims 11 to 23 wherein one or more of said distinct surfaces is formed integrally with said material support means. The conveyor of any one of Claims 11 to 22 wherein one or more of said distinct surfaces is a discrete element connectable to at least one of an other of said distinct surfaces or said material support means.

26. The conveyor of any one of Claims 11 to 25 wherein said conveyor is adapted to convey agricultural material.

27. The conveyor of any one of Claims 11 to 26 wherein said material receiving area includes an entry to one or more spinners, blending bins and/or blowers.

28. The conveyor of any one of Claims 11 to 27 wherein said material support surface is a substantially flat tray or platform.

29. The conveyor of any one of Claims 11 to 28 wherein said material transfer means include a plurality of spaced apart scraper bars, a longitudinal axis of each said scraper bar is orientated substantially perpendicular to a longitudinal axis of said material support surface.

30. The conveyor of Claim 29 wherein said scraper bars travel through a brushing means located at an end of said drop-off zone distal said material support surface.

31. The conveyor of Claim 30 wherein the base of said brushing means is inside the path of said scraper bars as said scraper bars travel over said drop off zone, and bristles of said brushing means extend into the path of said scraper bars.

32. A conveyor to deliver material from a material supply means to a material receiving area which, in use, is positioned below said conveyor, the conveyor including a material support surface, a material supply means proximate a first end of said material support surface and a drop-off zone at an opposite end of said material support surface, the conveyor further including a plurality of spaced apart material transfer means extending across the width of said material support surface and adapted to travel at least between said material supply means and a position at or substantially adjacent an end of said drop-off zone distal said material supply means, thereby transferring material from said material supply means to said drop off zone, wherein said material transfer means follow a substantially semicircular path over said drop-off zone, the drop- off zone including first and second distinct substantially flat or planar surfaces which together form a segmented convex surface extending, in use, below said material support surface, wherein the clearance between said distinct surfaces and said material support means allows said material, in use, to drop between said material transfer means and said distinct surfaces to said material receiving area at a substantially uniform rate.

33. The conveyor of Claim 32 wherein said drop off zone further includes a third distinct surface substantially adjacent said second distinct surface.

34. A conveyor substantially as herein described with reference to Figures 2A and 2B or Figure 3. DATED this 5 th Day of May 2003 BALDWIN SHELSTON WATERS Attorneys for: David Stanley Hoyle.